The present invention relates to bone implants, and also to a method of implantation, and to a kit for use in creating implant sites in bones. The invention is particularly useful in dental implants and is therefore described below with respect to this application.
Dental implants are increasingly being used where a patient requires a prosthetic device to bold one or more artificial teeth in place. Conventional implants include a cylindrical pin, usually of titanium but of other compatible material, formed with a threaded (or other shaped) bore implanted into the jawbone and covered by a temporary cap for a sufficient period of time to permit osseointegration of the implant with the bone, usually about three months for the mandible (lower jaw) and about six months for the maxilla (upper jaw). After this period of time, the cap is removed and the threaded bore is used to receive a post serving as an abutment which provides a support site for one or more artificial teeth.
The conventional dental implants, however, suffer from a number of drawbacks. Thus the strength and stabilization of the implant is greatly dependent on the anchoring method in the jawbone. For this reason, the bore drilled in the jawbone for receiving implant is as long as possible, generally extending through both the outer compact bone tissue and the inner medullary or soft spongy tissue of the jawbone. However, the latter tissue does not provide strong support for the implant, and therefore the implant may have insufficient strength and stabilization particularly with respect to patients having relatively shallow jawbones.
In addition, drilling long bores increases the danger of overheating during drilling, which could result in serious bone damage. Also, drilling long bores generally requires frequent raising and lowering the drill for cooling purposes, which can create misregistration in the resulting sections of the bore. There is also a danger of non-parallelism with respect to a plurality of implants and abutments, which could result in an unequal distribution of the stresses, overloading, and failure.